Method of manufacturing forming rolls



Sept. 16, 1952 w, 2,610,452

METHOD OF MANUFACTURING FORMING ROLLS Filed Sept. 25, 1950 5 Sheets-Sheetl 9 m'w;@4,b

Y Sept. 16, 1952 w. P. HILL 2,610,452

METHOD OF MANUFACTURING FORMING ROLLS 5 Sheets-Sheet 2 Filed Sept. 25, 1950 I WW,

INVENTOR.

Sept. 16, 1952 Filed Sept. 25, 1950 W. P. HILL METHOD OF MANUFACTURING FORMING ROLLS 5 Sheets-Sheet 5 ing operation.

Patented Sept. 16, 1952 METHOD OF MANUFACTURING FORMING ROLLS Walter P. Hill,

met & Hecla Pontiac, Mich., assi gnor to Calu- Consolidated Copper Company,

Calumet, Mich., a corporation of Michigan Application September 25, 1950, Serial No. 186,597 Claims. (01. 51-289) This invention relates to a imethodand apparatus for manufacturing forming rolls. More particularly the invention concerns itself with the manufacture of forming rolls composed of a plurality of separate discs supported on a shaft in juxtapositionwith the peripheral portions spaced from each other axially of the shaft to provide an annular groove between adjacent discs.

Rolls of the above general type are shown in the Walter P. Hill Patent No. 2,508, dated May 23, 1950; and are highly satisfactory for use in the production of tubing having an integral helically extending fin of substantial height projecting outwardly from the peripheralsurface of the tubing. In the manufacture of such finned tubing, three forming rolls are usually employed, and these rolls are rotatably supported with their axes. spaced from each other equal distances around a length of tubing. The axes of the rolls are inclined with respect to the axis of the length of tubing at an angle-corresponding to the mean helix angle of the fin to be formed on. the length of tubing, and the rolls are driven in tracking relationship about their respectiveaxesr r In operation, the rolls or peripheral edges of the discs apply a radially inwardly directed pressure on axially spaced helically aligned portions of the outer surface of the length of tubing, causing material from the outer surface of the tubing to flow or extrude outwardly into the annular grooves between adjacent discs. In cases where the helix angle of the fin is very small in order to obtaina large number of fin convolutions per unit of length of the tubing, and whrethe outside diameter-of the fin is large in" comparison to the root diameter of the fin, difficulty is encountered in passing the peripheral portions of the discs through othehelicoidalpath provided between adjacent convolutions of the fin being formed without displacing the fin convolutions axially of the tube. Such Minterferencecauses: the fin convolutions to move back and forth along the tube axis during the forming or rolling operation and not only unduly wears the roll discs, but in addition, work hardens the material to such an extent that any-attempt to raise a high fin from the tube fractures either orboth thefin and tube. The above objection may be overcome. by contouring the side surfaces of revolutionof the individual discs, so that the peripheral portions of the latter will pass relatively freely through the helicoidal path between adjacent, convolutions of the fin during theform- .In the Walter P. Hill was ridi'asoaeis the opposite side surfaces of revolution of the discs converge toward the outer edges of the discs and are convex in contour radially of the discs; This contour provides the relief required for the peripheral portions of. the discs to pass relatively freely through the helicoidal. path between adj acent convolutions of the fin, andthereby avoid the interference noted above. I

.Although forming rolls composed of contoured fin forming discs of the above type render it possible to produce integral high finned'tubing on a 1 production basis; difficulty has been encountered in forming the rolls with the accuracy required for optimum results. Owing to the fact that in such forming rolls the annular space existing between adjacent discs is very small, it is not feasible to provide a grinding wheel thin enough to operate within this space. Accordingly, it is not practical to form grind the discs while assembled in roll formation, and it has been the practice to individually form grind the discs prior to assembling the same. More particularly the work performin side surfaces of the. discs were form ground with reference to one. or both fiat ends of the hub portions of the discs, and the discs were grouped in assembled relationship'to, form facturing errors in grinding the individual discs,

although small, nevertheless become accumulative when the discs are secured in assembled relationship; and in some cases, the accumulative error which may be different for each roll of the series, is suificient to cause the interference discussed above between the discs and fin convolutions during the rolling operation.

' With the above in view, it is an object of this invention to simplify and reduce the cost of forming the roll discs as well as eliminate the accumulative error referred to in the preceding paragraph. This is accomplished according to the present invention by forming peripheral portions of a group of roll discs while the latter are supported in substantial spaced relationship in the same order they later assume when assembled to provide a forming roll. More particularly a plurality of disc blanks correspond- ,ing in number to the number of preformed discs template is provided for controlling the path of relative movement of the tool and arbor so that or contouring the the peripheral portions of the blanks are successively fashioned to the specified contour of the finished roll discs regardless of variations in thickness of the discs. The finished discs are then removed from the arbor and are secured together in juxtaposition in the same sequence they assumed during the forming operation. By following thisprocedure in forming each set of rolls employed to extrude a helical fin from a length of tubing, bending of the convolutions of the fin during the forming operation by reason of inaccuracies in the manufacture of the roll discs is reduced to a minimum. Also a superior finned tube is produced with less wear on the discs and maintenance costs are accordingly reduced. 1

It is a further object of this invention to provide an arrangement whereby one or more discs may be replaced in the group of discs forming the roll without destroying the accuracy of the roll.

In accordance with this invention, when it is desired to replace a disc, all of the usable original discs are again assembled on the tool arbor in the same relationship they assumed during the original forming operation, and the replacement disc blank is installed on the arbor in the position previously occupied by the disc it replaces. Thus all of the. discs are subjected to the finishing operation, so that the replacement disc or discs will have the remaining discs as the original discs.

The foregoing as well as other objects will be made more apparent as this description proceeds,

especially whenconsidered in connection with the accompanying drawings, wherein:

Figure l is a semi-diagrammatic plan view of same relationship to the apparatus embodying the features of this invenvtion;

Figure 2 is a sectional view taken on the line 22 of Figure 1;'

Figures 3, 4, and are respectively sectional views taken on the lines 3-3, 4-4 and 5-5 of Figure 1;

Figure 6 is a sectio 66 of Figure 1;

Figure 7 is an enlarged longitudinal sectional view through a part of a forming roll constructed in accordance with this invention;

Figure 8 is an enlarged side elevational view, partly in section, of shown in Figure 1;

Figure 9 is a sectional 9-9 of Figure 8;

Figures 10 and 11 are semi-diagrammatic views considerably enlarged to illustrate certain features of the apparatus shown in Figure 1.

The method and apparatus to be presently described in detail is particularly suitable for manufacturing forming rolls of the type shown in Figure '7 of the drawings and designated by the numeral I2. This forming roll comprises a drive shaft I3 and a plurality of discs I4. The discs are centrally apertured to receive the drive shaft I3, and are keyed or otherwise secured to the drive shaft for rotation by the latter. The discs I4 have central hub portions I5 of uniform axial dimension and have peripheral portions IS. The opposite side surfaces I! of revolution of the peripheral portions I6 converge from the hub portions I5 to the outer edge of the discs I4.

The discs I4 are assembled on the shaft I3 with the hub portions I 5 in contact and adjacent peripheral portions I6 cooperate with one another to provide annular grooves I8 therebetween. The number of discs I4 secured to the al view taken on the line view taken on the line a part of the apparatus 4 shaft I3 may vary to suit different conditions, but for the purpose of illustration, seven discs are shown. These discs are individually identified in Figure 7 of the drawings by the reference numerals I9 to '25 inclusive.

As disclosed in the Walter P. Hill Patent No. 2,508,518, a set of three rolls I2 are suitably supported around a length of stock or tubing, and cooperate with one another to extrude material from the outer surface of the stock to form a helically extending fin of substantial height on "the stock. The rolls are supported with their axes crossing the axis of the stock at an angle depending upon the helix angle of the fin to be formed on the stock and this angle is usually small in order to provide a large number of fin convolutionsper unit of length of the stock. The discs I4 on the respective rolls are in tracking relationship and the peripheral edges of at least the discs at the front ends of the rolls apply a pressure in a radially inward direction on axially spaced helically aligned portions of the outer surface of the stock. An opposite or radially outward force results from the application of said radially inward force on the stock and this outward force displaces or eXtrudes material from the surface portion of the stock outwardly between the axially spaced portions or into the annular grooves I 8 formed by the peripheral portions of the discs.

With the above in view, attention is again called to Figure 7 of the drawings, wherein it will be seen that the first four discs I 9, 20, 2I and 22 are the pressure applying or working discs; and the last three discs 23, 24 and 25 are more or less the finishing discs. The working discs I9 to 22 preferably progressively increase in diameter from the first disc I9 to the last. disc 22 of this groupin order to progressively displace material from the outer surface of the stock and at the same time, materially reduce the unit load on any one disc. The finishing discs 23, 24 and 25 may be practically the same diameter as the-final working disc 22 since the principal function of the finshing discs is merely to guide or straighten the fin convolutions formed by the working discs.

' The peripheral portions I6 of the discs I4 proressively increase in thickness from the first disc I9 to the final disc 25 with the result that the grooves I 8 progressively decrease in width from the first groove to the last groove. The purpose of this construction is to enable the side surfaces I1 of revolution to guide the material as it is extruded into a relatively thin high fin.

The helical fin produced with forming rolls of the above general type have adjacent convolutions closely spaced and of substantial height in comparison to the root diameter of the fin. The diameter of the discs I 4 is necessarily substantially larger than the outside diameter of the fin; and in practice, the rate of withdrawal of the discs from the spaces between adjacent convolutions of the fin is somewhat different than the rate of axial movement of the stock during the fin forming operation. This being the case, the peripheral portions I6 of the discs I4 interfere with the convolutions of the fin, and the latter are actually bent backwardly and forwardly during the fin forming operation. This is objectionable in that some work hardening of the material results, and considerable stress is applied to the peripheral portions of the discs. In order to overcome the above objection, the side surfaces of revolution of at least the working discs I9 to 22 inclusive are contoured in order is to 22 inclusive to pass relatively freely through the helicoidal path provided between adjacent convolutions of the fin being formed by the roll; In detail the surfaces of revolution H on'the working discs are convex and curve radially with respect tothe axis of the roll. This general elliptical curvature affords ample clearance tov enable withdrawal of the discs from the spaces between adjacent convolutions of the fin without appreciably bending or stressing'the'fin.

If desired the side surfaces of revolution of the siding or finishing discs 23 to 25 inclusive may correspond in contour to the'side surfaces of revolution of the working discs E9 to 22 inclusive. However, in the present instance, the opposite side surfaces of revolution of the sizin discs 23 to ad-inclusive are straight in radial contour as clearly indicated in Figure 7 of the drawings. Such a construction has the effect of work hardening the convolutions of the fine after they. have been discs, and in some instances, thisresultis desired. Inasmuch as the work place after the fin has been formed, it does not interfere with extruding the material to form a high fin. i

In the manufacture of forming rolls of the above type, it has been found that when the discs 14 are individually machined or formground to the specified contour without regard to ultimate assembled relationship, any error, no matter how slight, in the grinding of single discs becomes accumulative when the discs M are subseduently secured together toformla roll. 'Although the allowable tolerances in forming individual discs may be. small, nevertheless, the accumulative error over the group of discs. may be sufiicient to cause the discs to deform the fin during the fin forming operation. As a result such accumulative errors frequently promote work hardening of the metal during forming of the fin and cause excessive wear of the forming discs. a I

The foregoing is overcome in accordance with the present invention by providing a method and apparatus-for manufacturing the discs characterized in that the peripheral portions it of all of the discs it are fashioned or form-ground while the discs are supported in thesa'me relationship they subsequently assume when assembled to provide the forming roll l2. Also as formed by the working.

hardening takes will be more fully hereinafter described, the roll discs M are fashioned so that when they are assembled, the median planes of adjacent discs l4 are spaced equal distances from one another regardless of any variations in the thickness of the individual discs. Thus the grooves 68 are accurately located with respect to each other axially of the roll, so that little or no axial stress is applied to the material being extruded into the grooves it. Also when a plurality of rolls l2 are distributed about a length of tubing,v the grooves l8 accurately helically extending fin is produced with a minimum amount of resistance.

The various steps of the method of manufaoture will be more readily understood upon con* sidering one specific form of apparatus capable of carrying out the steps of the method With this in view, reference is made more in detail to Figure 1 of the drawings, wherein the numeral 39 designates a pantograph form grinder having a work holding assembly 3! and-having a forming tool assembly 32. The work holding assembly 3i comprises a base 33 and a compound slide 33' track and the desired suitably supported on the base. The compound slide 33" has. two slides. 34 and all. The slide 34 is adjustable relative to the base 33 in a longitudinal direction and. the slide 34' is adjustable relative to the slide, 34 in a direction extending transverse to the direction of movement of the slide 34. Suitable hand operated controls 35' and 35" are respectively connected to the slides 34 and 34 in a manner shown in Figures 2 and 6 of the drawings for independently adjusting the slides.

A spindle 35 is journalled in a bearing 36 suitably secured to the slide 34, in a manner such that the axisof the spindle extends in the direction of movement of the slide 34. The front end of the spindle 35 iscoupled to the drive shaft of an electric motor 31, and a suitable bracket 38 is provided for securing the motor on the slide 34.. The rear end of the spindle is provided with a center 38', which cooperates with a center 31' to, support an'arbor 3E. The center 31 is mounted on a'bracket 43 in axial alignment with the center 38, and the bracket 49 is suitably secured to the slide 34. The bracket it has a bearing part 4t within which the center 31' is supported for sliding movementv in the direction of its axis and a suitable hand operated control 4| is provided, for sliding the center 31. The arrangement is such as. to permit the arbor as to be readily inserted between and removed from the centers. The arbor 39 is rotated as a unit with the spindle 35 by means of a pin or lug 4! extending from the rear end of the spindle in a. position to engage a flat 42 (Figures) on the a jacent end of the arbor 39 The arbor 38 is shown in Figure 8 of the drawings as having a cylindrical part 44 projecting rearwardly from the head 43. The front side of the head 43 is fashioned with'a recess at the center for. receiving the center 38' on therear end of the spindle 35, and the rear end of the part 44 has a reduced threaded portion 45 which also has a recess at the end thereof for receiving the center 31.

The purpose of the arbor 39 is to support a plurality of disc'blanks 46 in operative relation to the forming tool 32. The disc blanks 43 are centrally apertured and are sleeved on the part 44. The first or forwardmost blank is seated against a stop in the form of an annular bearing surface 41 on the head 43 of the arbor, and spacer rings 43 are supported on the part as of the arbor between adjacent blanks in order to provide sufficient clearance between the blanks for the grinding disc 52. All of the disc blanks 46, together with the spacers 48, are clamped in assembled relationship against the head 43 by a cap 49 sleeved upon 45 in a position to engage the rear side of the last disc blank and held in place by a nut 5t threaded on the portion 45 of the part M.

The number of disc blanks M5 on the arbor 39 corresponds to the number of preformed discs l4 employed to form the roll 52, and inthe present instance seven disc blanks are shown. These disc blanks are individually indicated in Figure 3 of the drawings by the reference numerals it to 25 inclusive, and these blanks respectively correspond to the preformed discs 19 to 25 inclusive. The disc blanks ii; are rotated as a unit with the arbor 39; and for accomplishing this result, the cylindrical part 44 is provided with a longitudinally extending key 5! which extends into registering key slots formed in the respective disc blanks.

The forming tool assembly 32 comprises a the rear end ofthe part grinding wheel disc 52 secured to the front end of a spindle 53, and rotatable by the spindle in a plane normal to the axis of the arbor 39. The grinding wheel disc 52 is relatively thin, and is located by the spindle in a position opposite the arbor 39. The spindle 53 is driven by an electric motor 54 which in turn is supported on a slide 55. The slide 55 is supported for movement in opposite. directions normal to the axis of the arbor in order to permit movement of the grind ing wheel disc 52 in directions toward and away from the arbor axis.

As shown particularly in Figure of the drawings, the slide 55 is mounted on a second slide 56 supported on the frame of the machine for movement in opposite directions parallel to the axis of the arbor 39. Thus the grinding wheel disc 52, in addition to being movable toward and away from the axis of the arbor 39, is also capable of being moved along the axis of the arbor.

Such movement of the grinding wheel 52 relative to the arbor enables engaging the grinding wheel with opposite sides of the peripheral portions of successive disc blanks 46 on the arbor.

In accordance with the present invention, the path of movement of the grinding wheel discs 52 relative to the arbor 39 is controlled by a master cam or template 51. As shown particularly in Figures 1 and 3 of the drawings, the master template 51 comprises a flat strip positioned on the machine frame by pins 58 and removably secured to the frame by suitable fastener elements 59. The template 51 is spaced some distance from the arbor 39 and extends in the same direction as the axis of the arbor.

The inner edge of the template 51 is provided with a series of lateral projections 69 which are spaced from each other in thedirection of length of the template and correspond in number to the number of preformed discs I4 employed to form the roll I2. In the present instance seven projections are provided on the cam, and these projections are individually identified by the numerals I9" to 25" inclusive. The projections I9" to 25" respectively correspond to the peripheral portions l6 of the preformed discs I9 to 25 inclusive, and the edges or the profile of the projections are accurately formed to correspond exactly to the contour of the peripheral portions I6 of the respective discs I4. The size of the projections 60, however, is preferably many times greater than the size of the peripheral portions l6 of the discs I4 in order to facilitate manufacture. For the purpose of this illustration, the actual size of the projections 69 on the cam or template 51 is six times the size of the peripheral portions of the discs I4.. Also in the interests. of convenience in manufacture, the space between adjacent projections 6|! is a multiple of the space between adjacent disc blanks 36; and in the present instance, the space between adjacent projections 60 is six times greater than the space between adjacent disc blanks 46.

The master cam or template 51 is engaged by a follower 6| in the form of a pin, and the pin is in turn connected to the grinding wheel disc 52 by a pantograph arrangement of linkage designated generally by the reference numeral 62. The pantograph arrangement of linkage 62 connects the master cam or template 51 to the grinding disc 52 with a ratio of six to one. In other words the grinding wheel disc is moved throughout the path dictated by the master template at a rate which is A; the rate of movement of the follower 6| along the template with the result that the grinding wheel disc successively engages opposite sides of the peripheral portions of the blanks 46 on the arbor 39.

In detail the follower 6| is supported on the lower end of a link 63 and the upper end of the link 63 is pivoted by a pin 64 to the upper end of a link 65. The link 65 is the same length as the link 63, and is pivoted at its lower end to a bracket 66 rigidly fixed on the machine frame. The link 63 is connected to the slide by a link 68 positioned at the inner side of the link in parallel relation to the latter and having one end pivoted to the link 62 by a pin 69. The other end of the link' 68 is pivoted by a pin 16 to the slide 55 and to the inner end of a short link 1| having the outer end pivoted by a pin 12 to the link 65. The distance between the axes of the pins 16 and 12 is equal to the distance between the axes of the pins 64 and 69. Also the distance between the pivot pins 64 and 12 is the same as the distance between the pins 69 and 16, with the result that a parallelogram is formed. In addition it will be noted that the distance between the pivot pins 14 and 69 is equal to one sixth the length of the link 63. As a consequence movement of the follower 6| in and out relative to the master cam 51 moves the grinding wheel 52 or slide 55 through the medium of the parallelogram linkage previously described in corresponding directions at a rate one sixth the rate of movement Of the follower 6| Likewise any displacement of the follower 6| back and forth along the master cam 51 causes the parallelogram linkage to apply a side thrust on the slide 55 which is transmitted to the slide 56. Thus the slide 56 moves the grinding wheel 52 or slide 55 back and forth along the arbor 39 at a rate one sixth the rate of movement of the follower 6| relative to the cam 51.

The numeral 15 in Figure 1 of the drawings designates a dressing device for the periphery of the grinding wheel 52. Briefly th dressing device 15 is supported on the machine frame at the side of the grinding wheel spindle 53 opposite the side occupied by the arbor .39. The device 15 comprises a slide 16 and a, dressing tool 11. The slide 16 is supported on the machine frame for movement toward and away from the grinding wheel spindle 53; and the tool 11 is supported for rotation in a plane normal to the plane of rotation of the grinding Wheel 52, The slide 16 is movable toward and away from the periphery Of the grinding wheel 52 by a hand wheel 18 mounted on the outer side of the machine frame in a position where it may be conveniently manipulated by the operator.

The dressing tool 11 is positioned to require movement of the grinding wheel 52 forwardly and outwardly from its normal operating position relative to the arbor 39 in order to bring the periphery of the Wheel 52 in operative relation to the tool 11. Movement of the wheel 52 to its dressing position is facilitated by providing a hole 19 in the machine frame for engagement with the follower pin 6|. In this connection it will be noted that the pin 6| is slidably supported on the outer end of the link 63 to permit dropping the same into the hole 19. The hole 19 is so located that when the linkage 52 is operated by placing the follower 6| into the hole 19, the grinding Wheel 52 is moved from its normal position shown by the full lines in Figure 1 to the dressing position shown by the broken lines in the same figure. After the grinding wheel 52 is located in its dressing position, the hand Wheel 18 is manipulated to bring the point of the withithe: details of iniregistrationv with the portions of the blanks other so that c exist in the thickness of that upon completion of 9 I tools-.11? into 1.enga;g'ement with the periphery of theigrinding-wheeland the tool 1 HS alternatively rotated in opposite directions byaahandoperated control '80 to. dressitheirperiphry 'of'thei wheel 52-; J The dressing device'an'dthe means :ior oper ating-.the same is merely: diagrammatically illus= trated hGi'BihQaS thisrinvention isnot concerned construction of thesamen 1 c v Operation The first step in the operation after an arbor 39 with a set of disc blanks 46 is supported on the centers 31p and 38',;is to rest the follower ti on the extreme inner edge of the first master cam projection l9". This movement of the follower 6! through the linkage 62 *shifts the grinding wheel52 rearwardly and inwardly-relative to the arbor 39 to. locateithe periphery ofithe wneei'sz firstz..disc"iblanli l on the arbori- 3.9.. The compoundslide' of tliiiiiiik holder assembly 31 .is then adjusted relativeto the 'grinding wheel disc 52 vto bring the peri hery of the. wheel $52 into grindingxcoii'tact with the periphery-of the first disc blank l9 and the disc 19' 'lisiiground to the-desired:diameter? Upon completion ofthe-above operation the follower- 6i is shifted to the' brokenlinefposition shown in Figure 1 and the work holder 31' is again adjusted until the front side of the wheel 5'2 sparks against the rear side of the first disc IS. The arbor 39 and grinding wheel 52 are then in their proper relative positions, and the 'iollower 6| is manually moved successively along the profiles of the cam projections 19" to 25". Owing to the pantograph linkage connection 82 between the follower 6| and the grinding wheel 52; the latter successively engages opposite sides of the disc blanks 46 and forms the peripheral to the exact profile contour of the cam projections 60. This operation is illustrated inthe exaggerated views (Figures 10 and 11 of the drawings), and attention is called to the fact that the disc blanks 4G and cam proje'ctions B0 are axially spaced relative to each the median planes P between the opposite side surfaces of adjacent discs M of the roll 12 are predeterminedly spaced, or in the presaeronee onecr more vCir ent instance, are spaced equal distances from one another regardless of any variations that may the discs l4. As a result when the rolls l2 are distributed around alength of tubing, the grooveslB are arranged in ac-, curate tracking relationship and material is extruded from the tubing by the roll discs M with a minimum amount of resistance.

It will be apparent from the above that the peripheral portion of each disc blank on the arbor is ground to the exactcontour of its corresponding cam projection on the master cam 51. The profile contour of the cams 19" to 25" in turn respectively corresponds to the predetermined contour of the roll discs 19 to 25 so the grinding operation on the blanks [9' to 25' inclusive, one complete set of roll discs I4 is provided. These discs are then removed from the arbor 39, and are assembled as shown in Figure 7 of the drawings on the shaft [3 in the same sequence they previously occupied on the arbor 39. Thus when a plurality of rolls l2 formed in the above manner are grouped around a length of stock to be finned, the spacing between adjacent side surfaces of revolution of corresponding discs of the rolls in the group is the same and fins of substantial height may be more accurately extruded from the 10"? periphery of the stock with the Z'minimum applied :to the individual discs. i v 1 I c "Also with the abovefimethod an .:apparatus .of the preformed discs 1M "maybe replacedcwithout destroying theja'ccuracy. of the relationship described ino the :preceding -,para,- v graph: Assuming. for the purpose of illustration that it is desired tooreplace" the forming disc 22' of theroll I 2,.all of 'thedis'cs fl tare removed from the shaft [3 and with the exception of. theidisc 22 are assembled in the. same sequence-phi the arbor 39. A disc z'bla rk 22"';.is. substituted for the v preformed disc. are dthe grinding :operation described above is repeated; 'During;thi s -grinding operation the blank 22; is fashioned ;to' the contour of the disc 2'2'and the amount of stock removed frtinr theidiscs'l 19;

again assembled on: therollishaft l3; i

What];- claimias myginvention is: 1.311: the manufacture of a forming up. of a plurality: of individual.

roll inadeprovide annular grooves therebetween .off a width less than theclearance'reqiiired for operation of a materia'lrerhcving tool, the method which consists in securing a plurality ofdiscz blanksion an arbor withiadjacent blanks spaced'airom-weach between adjacentblanks, and guiding relative movement of the arbor and tool to successively form the peripheral portions of the blanks to a contour which corresponds to the contour of the peripheral portions of the forming roll discs and in the same sequence the contoured discs assume in the completed roll. I

2. In the manufacture of a forming roll made up of a plurality of individual axially aligned discs having the peripheral portions preformed to provide annular grooves therebetween of a width less than the clearance required for operation of a material removing tool, the which consists in securing a plurality of disc blanks on an arbor with adjacent blanks spaced from each other axially of the arbor a distance which is substantially greater than the distance between adjacent formed discs when the latter are assembled to make up said forming roll, successively forming the peripheral portions of the disc blanks to a contour which corresponds to the contour of the peripheral portions of the forming roll discs, and thereafter removing the formed discs from the arbor and reassembling the discs in the same sequence the disc blanks assumed during the forming operation to provide said forming roll.

3. In the manufacture of a forming roll made i up of a plurality of individual axially aligned discs having axially spaced peripheral portions or" different cross sectional contour and being spaced from each other a distance less than the clearance space required for the operation of a material removing tool, the method which comprises securing a plurality of disc blanks on an arbor with ad acent disc blanks spaced from each other stress 20, 2|, 23,24 and 25 is sufficient: only to: insure obtaining, the desired relationship between the; discsaszwhenl'they are axially aligned discs having the peripheral: portions preformed'to' method,

successively forming the peripheral portionsfof:

sequence'the finished discs assumein the;com-.-

pleted roll. V V V,

4'. The method defined in claim 3 having the additional step 01' removing the formed discs from the arbor and reassembling the discs in the same sequence the blanks assumed during the forming operation to produce said forming roll. 5. In the manufacture of a forming roll made up of a plurality of individual axially aligned discs having contoured peripheral portions which progressively increase in width axially of i the roll to provide: annular grooves of" progressively decreasing width between adjacent peripheral portions, the method which comprises securing on the arbor a group of discs which correspond in number to the number of the forming roll discs and spacing the discs equal distances from each other on the arbor with sumcient clearance between adjacent discs to receive a forming tool, successively moving a forming tool over the peripheral portions of the blanks to fashion the 12' oppositesides and the outer edges of the blanks, guiding movement. of the tool! along successive paths which respectivelycor'respondi in contour operation. l

V WALTER P. HILL. REFERENCES CITED,

The following references are of recordin the file of this patent; v UNITED'ST ATES PATENTS Number Name. 1i Date 983,828 Lentz Feb. 7, 1911 1,844,566 .Dienes Feb." 9, 1932 7 2,203,200 Komarek June .4, 1940 2,279,523 "Rickenmann Apr. 14,; 1942 2,291,073 Dodge July 28; 1942 2,337,016 Hillix et a1. Dec. 14, 1943 2,379,419 Atti. June 3, 1945 2,394,671 Duncan Feb. 12, 1946 2,429,491 Schuler Oct. 21, 1947 2,434,834 Givitarese Jan. 20, 1948 2,472,975 7 Houghtaling June 14, 1949 

